Performance Of Sodium Olefin Sulfonates And Mixed System

Sodium olefin sulfonates, a kind of excellent anionic surfactant, have not only great wetting and detergency properties, but also outstanding biodegradability and salt tolerance.Due to these advantages, sodium olefin sulfonates have been widely applied in various prospects such as washing and enhanced oil recovery. The hydrophobic group and hydrophilic group of surfactant are two main factors influencing its performance and application. In this thesis, three different chain length sodium ?-olefin sulfonates (CnAOS,n=14-16,16-18, 20-24) and sodium internal olefin sulfonates (C16-18IOS) were chosen as the research object to study the structure-performance relationships, the properties of mixed system of sodium internal sulfonates and fatty alcohol polyoxyethylene ether(AEO9), and the influence on emulsion polymerization. There are three main parts in this thesis as follows:1. The effect of hydrophobic chain length and hydrophilic position of sodium olefin sulfonates on the surface and interfacial properties, wettability, salt tolerance, foaming and emulsifying properties were studied. Results show that critical micelle concentration (cmc)and diffusion coefficient of sodium olefin sulfonates decrease, and surface tension at cmc(?cmc) and contact angle increase with increasing hydrophobic chain length. As the hydrophilic group is moved from a terminal position to a central position, cmc and diffusion coefficient of sodium olefin sulfonates increase, and ?cmc and contact angle decrease. Interfacial tension decreases in the order C16-18IOS > C16-18AOS > C20-24AOS >C14-16AOS. Salt tolerance of sodium olefin sulfonates decreases with increasing hydrophobic chain length. As the hydrophilic group is moved from a side position to a central position, salt tolerance of sodium olefin sulfonates increases. Foaming property of C16-18AOS is better than other three sodium olefin sulfonates. Emulsifying property of C14-16AOS is the best and emulsifying property of C16-18AOS is more excellent than that of C16-18IOS.2. Surface property, wettability, foaming and emulsifying properties of the mixed system of sodium olefin sulfonates and AEO9 were investigated. Results show that the mixed system has synergism in micelle formation when the mole fraction of AEO9 is 80 %and negative synergism in surface tension reduction effectiveness when the mole fraction of AEO9 is 20%. Wettability, foaming and emulsifying properties of the mixed system are between the performances of two single components.3. The influence of sodium olefin sulfonates and the mixed system on styrene-acrylic emulsion polymerization were investigated. There is no obvious distinction in latex particle size and electrolyte stability of polymer emulsion decreases with increasing hydrophobic chain length of AOS. As the hydrophilic group is moved from a terminal position to a central position, latex particle size decreases and electrolyte stability of polymer emulsion has no significant changes. Compared with single sodium olefin sulfonates, the mixed system reduces latex particle size and enhances electrolyte stability of polymer emulsion.